1. Field of the Invention
The present invention relates to a waste water treatment apparatus.
2. Description of the Prior Art
Nowadays, water source is more and more valuable. How to circulate water and reuse waste water is a topic for discussion. Referring to FIG. 1, a conventional waste water treatment system 10 disclosed in U.S. Patent Application Publication No. 2008/173581 A1 comprises a waste water storage tank 11, a treatment vessel 12 and a treated water tank 13. The waste water storage tank 11 is used to store the domestic waste water. The waste water flows to the treatment vessel 12 through an inlet pipe 111 for treatment. The treatment vessel 12 comprises an activated particles layer 121 and a sand layer 122 therein. The water is first treated by the microorganism of the activated particles layer 121 to absorb the impurities of the water, and then filtered by the sand layer 122. The filtered water flows to the treated water tank 13 through a drain pipe 123 for use. Furthermore, the treated water tank 13 is communicated with the treatment vessel 12 through a pressurization pipe 13.
The activated particles layer 121 of the conventional waste water treatment system 10 must be continuously mixed during operation to get a better absorption effect. It is required to replace the microorganism of the activated particles after a period of use. The sand layer 122 is able to separate the impurities, but the impurities will be kept on the sand layer 122. After a period of time, the sand layer 122 will be clogged by the impurities and the water cannot pass the sand layer 122. It is necessary to start the pump provided in the treated water tank 13 to pressurize the treated water, and the treated water flows back through the pressurization pipe 14 to the treatment vessel 12 to disturb the sand layer 122, so that the sand layer 122 can restore the filtering effect again. The gravel sand of the sand layer 122 will be gradually decreased after cleaning many times. It is necessary to resupply or replace the gravel sand. When cleaning, the treated water may be used, which lowers the efficiency of the waste water treatment system. Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve this problem.